Process of treating metal surfaces



Patented Oct. 10, 1922,

HERBERT G. GRANT, OF ATTLEBORO, MASSACHUSETTS, AS$IGNOR TO 5'. 0. BIGNEY Cc COMPANY, 01' ATTLEBORO, MASSACHUSETTS, A CGRE-ORATION 03: IYJIASSACHUSRTTS.

PROCESS OF TREATING METAL N 0 Drawing.

To all whom it m y concern Be it known that I, HERBERT G. GRANT, a citizen of the United States, residing at Attleboro, in the county of Bristol and State of Massachusetts, have invented certain new and useful Improvements in Processes of Treating Metal Surfaces, of which the following is a specification.

This invention relates to a new and improved process for producing highly ornamental effects on metal surfaces, such effects as to resemble ribbed-silk in colors, oriental or Persian eifects, or other desired effects produced by various combinations of colors upon such metal surfaces; and the object of the invention is to produce these difierent ornamental effects by depositing gold or other metals of different colors in different layers to produce various combinations and then subject the surface so treated to a process of forcing portions of the colored patterns below their normal surface, or by raising a multiplicity of protecting ribs through such surface, which effects in some cases may be produced by a so-called engine turning operation thereby adding to the highly ornamental effects on the metal and at the same time protecting the deposited colors rendering the surfaces so treated very durable as these raised ribs serve to effectually protect the depressed colored portions thereof.

It is well known in the art that fine gold may be produced in addition to its natural color, in a limited number of other distinct colors such as red, white, and green, and I have found that these colors may be de posited electrically in different layers onto the surface of metal to produce highly ornamental and effective designs, and the following is a detailed description of one method by which my improved result may be produced.

I first deposit either electrically or otherwise upon a metal surface a layer of gold of a certain color; I then deposit a protecting covering upon that portion of the first colored layer which is to be preserved as a part of the design when the article is completed, which covering prevents the color from taking on other colors during subse quent depositing operations. I next deposit another color over the surface to be treated.

Application filed May 20, 1921. Serial No. 471,192.

I then deposita protecting material. over that portion of the second color which is to be preserved in the design. I then deposit a third color over the surface to be treated. I finally remove the protecting material from all of those portions which were covered with the same, exposing the various previously protected colors of the design.

I do not limit myself to the employment of just the limited number of colors above enumerated as still other colors may be deposited. and covered with a protecting material in the manner described. without departing from the spirit and scope of my invention.

After depositing all or any of these colors in the manner above described to produce the desired design and ornamental effect I next subject the surface to another step in the process by whichparts of the colored portions of the surface are depressed below their normal plane or below adjacent parts thereof. In other words a multiplicity of protecting ribs are raised through the treated surface, which results may be accom plished by what is known as an engine-turning process or operation, which operation serves to iron, press or force portions of the colored surface into narrowly spaced apart grooves below their normal level thereby effectually preserving the design of colors as they are depressed below the wearing surface of the resulting raised portions or ribs, rendering the design produced by In process very durable and practically indestructible.

I have described the depositing of gold of various colors, but I do not wish to be restricted to the use of gold alone as other metals of different colors may be employed in my new and improved. process in which a great variety of effects may be produced by alternately depositing layers of different colors and between which layers I deposit a protecting material over those portions of the different colors to be preserved in the design after which I remove the protecting material and treat the colored surface to an engine-turning operation.

My improved process is extremely simple and practical and by its use highly ornamental surfaces of appropriate designs may be produced on many articles of jewelry as Well as on Watch eases, cigarette cases, vanity oases and a great variety of other ftllZ-lPlGS rendering; them highly ornamental' I claim:

An improved method of producing; an or nainenl'al effect on metal surfaces, which consists in electrically depositing a plurality of layers of metal lilms upon a metal plate, eoverin that portion of saitl plate with a 10 rotectin material between each two a)- plications of metal films which is to be preserved in the design, subsequently removing the protecting material and forcing or press ing portions of the layers below their normal or deposited surfaces and raising protecting portions of metal between said clepressed portions.

In testimony whereof I affix my signature.

HERBERT G- GRANT. 

